Combination bow and multiple cantaliver vehicle-spring.



COMBINATION F. N. SPRAGUE.

BOW AND MULTIPLE CANTALIVER VEHICLE SPRING.

APPLICATION FILED APILG, 1915.

Patented Deo. 28, 1915.

Specification of Letters Patent.

Patented Dec.. 2%, i915.

Application filed .[iprl 6, 1915. 'Serial No. 19,4175.

2' 1o all whom 'it' 972,655.1/ conce/m Be it l-rnown that l, FRANK SrRAeUn, a citizen ot the TUnited States of America, residing at Sedgwick, county ot Sedgwick, and State of Colorado, hare invented a new and useful Combination Bow and Multiple Cantalirer Vehicle- Spring, of `which the following is a specitication.

This invention relates to improvements in a combination how and multiple cantaliyer `vehicle spring and more particularly in springs designed tor use in connection with automobiles and the like, the said invention being designed as an imprmT nient upon a spring for which an application was allowed to me on the 25th day of September, 191.4, hearing serial No. 767,662, which application issued April 6, 1915, as Patent No. 1,131,927.

The object or" the invention is to provide a spring of this character, which is so constructed that its resiliency is automatically increased or diminished to meet the demands ot varying road and load conditions. Further, to provide in connection with a semielliptical or three quarter elliptical spring, supplemental sijning members so arranged and connected as te provide a springv of the cantaliyer type, the resiliency whereot is auton'iatically increased or diminished under Varying load and road conditions, means being employed iior manually determining the degree of stillness under which the springs shall act. rllheseolojects are accomplished loy the construction illustrated in the accompanying drawings, in which:

Figure l, is a side elevation showing my improved supplemental spring used in connection with the ordinary `semi-elliptical side spring, as applied to the rear axle oit an automohile,the rear portion et one ot the side bars of the chassis being shown in connection therewith. Fig. 2, is a similar View showing` the arrangement or' the spring as applied to the front axle and forward portion of the side bar of the chassis. Fig. 3, is a side View showing the supplemental spring used in connection with an ordinary hree-Yquarter elliptical spring as applied to the rear axle of an automobile vand the zhassis. Fig. it, is a vertical, transverse sectional View on the line L -4r of Fig. 3. And Fig. 5, is a sectional View illustrating a modification in the fulcrum.

Similar letters'oi' reference refer to simi lar parts throughout the several Views.

teierring to the accompanying drawings, the numeral l indicates a portion ot one of |'he side hars of' the :trame or chassis ol an automobile, trie said har being ar anged at its rear end to accommodate a semi-elliptical spring ot the usual type.

2 refers to the rear axle; 5 refers to a seat ot the usual type, which is holtand receiving nuts 8, by

eat The spring leaves are further held a. nst endwise movement hy a bolt 9,

which passes up through the leaves, and through the plate 5, and receives a nut l0. The ttor fard end ot the spring is connected to the upper end oi2 links ll, the lower ends ot which pivotally connected to the side har t.

The construction and arrangement oit' the spring thus vlar described, is in no way ditterent from springs of this character in common use. '.lhe opposite end ot the spring, howeier, is not directly connected with the side har hut indirectly connected therewith hy supplemental sp ings which cooperate 'witli the main spring to provide the maximum re iliency without increasing the length oi the spring diminishing its streneth, the arr iig-ement ot' said supplemental springs being follows: ils eooce stated, the rear end ot the main semielliptical spring is not attached the side frame, and to this end ot the spring is se cured one end of a supplemental spring l2, which m made up oi a sutlicient ninnher ot loaves to give it the required strength and stillness, only two leaves however being illustrated. The connection is made hy passing a holt i3, through ears ll, formed on the under or longest leaztv oit the spring 12, and thi-curdi the eyed end ot upper or longest leali ot the main spring. The opposite end ot the spring lf2 is connected to links 15 hy a holt 1G, the upper ends olf said links heing piyetally attached to the adjacent end oit the lower lea't et the main spring.y by a holt 17 the said end ot the spring being fil titl

bent to form an eye to receive the said bolt. A spring 18, similar to the spring 12, i.y also supported at one end by the bolt 16, the upper or longer leaf of said spring having ears 19 through which the said bolt passes. The opposite end of the spring 18 is connected to the upper ends of linlts 2O by a bolt 21, and the lower ends of the links are pirotally connected to the side bar 1 by a bolt 92. ,`he ends of the springs 12 and 18 are separated only by a` short space, but the spring 18 has a slightly greater curve than the spring 12, whereby the space between them increases tof'ard a point midway between their ends.

rlhe stiffness of the springs 12 and 18 with respect to each other, is determined by an adjustable fulcrum, which determines the point beyond which the springs are spreadA under a load or under a jolt. This fulcrum comprises a U-bolt or clevis 2l, the closed end of which rests in a transverse semicircular recess in a block 25, which is secured to the upper leaf of the spring 1Q, by a bolt 2G, which passes through the blocli and through both leaves of the spring. A block 27 having a transverse semi-circular recess, is secured to the under leaf of the spring 18 by a bolt 28. A plate Q9 having a blade or rib 30, rests against the under side of the block 2G, the blade on said plate bearing in the recess of the block. The ends of the plate .Q9 are aj'iertured to receive the threaded ends of the clevis 21, and upon these threaded ends of the cleris are screwed nuts 31, which bear against the under side of the plate 29. By adjusting nuts 31, the tension under which the springs 1Q and 18 are held may be varied to obtain the requisite amount of stiffness to meet the required load conditions, as will be hereinafter more fully explained. The supplemental springs may also be used on the opposite or forward end of the main spring, as shown by dotted lines in Fig. 1, or they may if desired to be used in connection with bpth ends of the main spring.

ln F 2, l have illustrated the arrangement of the spring as applied to the forward axle 32. The main spring 33 in this case is similar to the spring el in Fig. 1, its forward end being secured in the usual inanner, to the forward end of the side bar 1. The supplemental springs 34k and 35 in this case are in all respects similar to the corresponding springs 12 and 18 shown in Fig. 1, and are connected to the spring 33 in the same manner in which the springs 12 and 18 are connected to the spring 4.-. il link 36 of suitable length connects the rear end of the supplemental spring 35 with the side bar. The action of the front and rear springs however is precisely similar. i

In Fig. 3, supplemental springs 37 and 3S are shown in connection with a three-quarter elliptical spring comprising a lower spring member 39, like the springs l anc 33, and an upper spring member l0, which is secured at its inner end to the rear end of the side bar 111, in the usual manner in which such spring members are connected. The supplemental springs 37 and 38, in this adaptation, are secured to the main spring 39 in the same manner as in the case of the similar springs shown in Figs. 1 and 2. The rear end of the spring .38, however, carries depending links 12, which are connected thereto by a pivot bolt 413, and the under or longest leaf of the spring a0 is curved around and under the ends of the springs 37, 38 and 39, and is connected to the lower ends of the links 112- by a pivot bolt eil. The arrangement of the supplemental springs as illustrated is such that only the ends which are connected respectively with the end of the main spring and the side bar, are subjected to load strains, but the springs are bent or bowed thereby throughout their length, under such strains, the fulcrum 2st determining the point beyond which the said springs spread. Between the fulcrum and the fixed ends of the springs, the bowing of the springs causes them to approach each other, and finally to touch, when the jar or load is greater than that exerted under average conditions. Thus the full resiliency of the springs is exerted up to the point where they are bowed sufficiently, under jolt or load strains, to cause them to touch between the fulcrum and their fixed ends, after which their resiliency is checked or in other words the springs begin to stiften, and this stiftening increases as the load strain increases from the fact that the added strain causes the springs to engage along a greater length of their surface, thus coniining their spring action to the area between their point of contact and their outer ends. Under rebound,

the supplemental springs exert a lifting v power up to the point when the body of the vehicle reaches its normal level with respect to the main spring, when the outer endof the lower supplemental spring engages the end of the upper supplemental spring, which is bolted to the adjacent end of the main spring; the action of the supplemental springs then ceases, and the rebound is checked thereby, and absorbed entirely by the main spring. The fulcrum may be placed at any point between the ends of the supplemental springs, which will effect the best results, and by turning the nuts 31 to bring the supplemental springs closer together stiffer spring action is obtained, as closer proximity of the opposing faces of the said springs causes them to engage more quickly and before the springs are bowed, as greatly as they would necessarily be if they were farther apart. lVhen closer together they also lengage throughout a greater incassa length under less curvature, thereby decreasing` the full spring action or resiliency. By confining the springs at one end and holding them against spreading at an intermediate point between the iixed ends and the load sustaining ends, a spring ot the cantaliver type is obtained and one in which the resiliency is automatically increased or diminished to meet the 'varying road and load conditions. The blocks which support the clevis or 'tnlcrum and the plate 29 permit a slight rocking movement ot the parts ot the tulcrnm with respect to one another, under the bending or bowing` action ot the springs.

in Fig. l I have shown a modilication of the nlcrnm, in which the plate 29 is dispensed with and a groored block l5 is employed, similar to tlie blocks 25 and 2S, through which the ends ot the elet/'is extend. The groove in the bloei; faces the groove in the block Q8, and a roll 46 is placed in these grooves, which permits tlie desired rocking movement ot the parts.

lil-aiding; describefil my inrentien, what l: claim as nen' and desire to secure bv Letters uPatent, is:

l. The combination withl a vehicle aid and side bar, oit a main leat spriifig` secured siibstantialli7 midway et its length to said afd-i and at one end to said side bar, a pair of supplemental. springs which are connected at one end b); a common bolt and links connecting` said bolt With the under side of the main spring adjacent the axle, links and bolts connecting the "free end oit the under supplemental spring' with the side bar. a bolt connecti g the ree end et the upper spring with the tree end ot the main spring', and means for preventing spreading ci said spri1 beyond a iredetermined intermediate point.

The combination with a vehicle axle and side bar, oi" a main leaf iring secured substantially midwajg7 olf its` length to said axle, a pair et spaced supplemental lea't springs secured at one end upon a common bolt, and links connectin' said bolt with the eg" V mam spring' adiacent ene ale, adjustable means 'for maintaining; a space between said springs at a point intermeniate ot their ends, means connecting,` the tree end et the upper with the tree end et the main spring, and means connectingthe vtree end ol the neder springVIN with the side bar.

3. The combination with a Vehicle axle ind side bar, of a main lealI spring secured aibstantially midiva,T et its length to said aide and at one end to said side bar, pair of spaced supplemental springs secured at their inner ends upon a common bolt, and a lint: connection between said bolt and the under leat ot said main spring, adjustable means tor bindine' said springs at a point intermediate ot their ends, and means for securing t tree ends ot said springs respectiif l to the side bar and to the tree end ot the main spring.

The ccnnbination with a 'vehicle axle and side bar. of a main leaf spring secured substantially midwa)v7 ot its length to said axle and at one end to said. side bar, a pair oil' spaced supplemental leaf springs secured upon a common bolt at their inner ends, and a link connection between said bolt and the main spring' adjacent the axle, tnlcrnm secured upon the springs at a point intermediate ci" their ends, and comprising a greeted block which is secured to the upper tace et the upper spring, a grooved block sccnrwl to the lower tace of the lower spi-ingr, a plate having' a bead which rests in the groove ot the loner bloeit, a clei'is the closed end ot which rests in the groote oi the upper block, Wliil its threaded e5;-

remitiee extend through openings in the plate having trie bead, and receives clamping nuts, a bolt connecting the tree end ot the ripper spring with the t'ree end of the main spring. and a bolt and link connection between the treeend of the Under spring and the side lar.

5. The combination with a ifehicle axle and side bar, ot a nain leal spring secured to said aille substantiall't7 midway oi2 its length and hinged at one end to the side bar, a pair ot supplemental leaf springs baring the saine general carre as the main spring and secured at their inner crd on a coininen bolt, means ter liinging said springs to the under side cit the main spnng, a hinge connection between the tippe' snpn'ieiral spring` and one end ot the main a hinge connection betr-fee the other nental spring' and the side bar, and a :nred around the supplemental vl`mediate oit their ends, whereby ,mi on the enter ents ot said supplemental springs cans 3 them to bend throughout their lengths WherebgT they are brought into engagement between their inner 'v antV1 tbe ifincrnni thns causing),v a sti eninp; their action in proportion to the strain.

ln testimoniY whereof It atto: my signature presence of two Witnesses.

FEL-Ulli N. SPRAGUE.

lilitnesses G. SAnGnNT ELLIOTT, Hensel-zr L, CHASE.

Copies of this patent may be obtained for ve cents each, by addressing* the Commissioner of Patents, Washington, C. 

